Isopropyl alcohol (IPA), or 2-propanol, is commonly used as a solvent and/or drying agent in many industrial applications. For example, IPA is used in deionized water in many semiconductor processing facilities to reduce surface tension in a finishing rinse to clean silicon wafers. Both liquid and gas-phase IPA-laden waste streams are often generated. Limitations are placed upon the amount of liquid IPA that may be introduced into the publicly owned treatment works (sewer), often in conjunction with the requirement to pay fees proportional to the amount of organic carbon associated with the IPA being released. In addition, the resultant IPA-laden gas stream must be treated before being discharged into the environment.
A variety of treatment mechanisms have been used to treat IPA-containing gas streams. However, none have provided a cost- and materials-effective solution. Known procedures typically have high consumption rates of water and other materials, require frequent maintenance and cleaning, or require expensive equipment and/or materials.